1. Field of the Invention
The present invention is concerned with novel, low cost, support, drainboard and seal devices designed for use between drift eliminator packs of large industrial water cooling towers in lieu of complicated, expensive, custom-fabricated wooden assemblies traditionally employed in this context. More particularly, the invention pertains to unitary, synthetic resin support, seal and drainage devices which can be interposed between eliminator packs using a minimum of on-site labor with consequent significant cost savings; moreover, the unique drainage tray forming a part of the invention collects and concentrates eliminated water droplets into relatively large streams which are resistant to reentrainment in air currents passing through the tower.
2. Description of the prior Art
Crossflow water cooling towers broadly are comprised of an elevated hot water basin together with underlying fill structure and a lowermost cold water collection basin. Means such as powered fans are used to draw air currents through the fill structure in intersecting relationship to descending hot water from the hot water basin. Initially hot water is dispersed in the fill structure and is evaporatively cooled by the crossflowing air currents.
Such towers also conventionally include drift eliminator assemblies positioned adjacent the inner faces of the fill. Commonly, such drift eliminators are in the form of upright, obliquely oriented, superposed sections or packs which cooperatively extend the full height of the fill. The purpose of these drift eliminators is to remove entrained air droplets from the crossflowing air current prior to discharge thereof into the atmosphere; in this way the tower discharge does not contain objectionable amounts of water which can lead to corrosion problems on adjacent structures and equipment, or to environmental concerns because of minerals or organisms in the water. A variety of eliminator designs have been proposed in the past, such as the so-called "cellular" eliminators disclosed in U.S. Pat. No. 4,514,202. These eliminators are extremely efficient from the standpoint of water droplet removal.
In the fabrication of water cooling tower drift eliminator assemblies, a problem is presented at the region of the joints between vertically adjacent eliminator sections. That is to say, it is necessary that these elongated, transverse joints be sealed to prevent the passage of moisture-laden air currents therethrough, which of course would not be subjected to the effects of the eliminators. At the same time, the eliminator sections (which can be relatively large in the case of industrial towers) must be adequately supported. Finally, it is very desirable to properly drain water gravitating from the eliminator sections in a manner to ensure that such water is not immediately reentrained in the crossflowing air currents passing through the tower.
In the case of towers making use of wooden structural girts and uprights, the conventional practice has been to custom-fabricate wooden support, drain and sealing devices between adjacent eliminator sections. Generally speaking, this has involved fabrication of joint-sealing plates along the air exit faces of the adjacent eliminator sections of a height to cover the joint and to prevent leakage of moisture-laden air therethrough. The drainage function has been performed by a obliquely and outwardly extending plate or plates positioned beneath the lower margin of each individual eliminator section. These sealing and drainboards are in turn supported by a series of specially fabricated wooden beam and planks which typically must be sawn at relatively critical bevel angles and carefully positioned and secured in place upon installation.
In addition, use of oblique, planar drain boards between the fill sections has resulted in water drainage in the form of small streams or a thin sheet from the lower margins of the drainboards. Such a drainage pattern is susceptible to substantial reentrainment of water droplets as they descend toward the underlying fill. As a consequence, the effectiveness of the overall drift eliminator assembly of the tower has been compromised.